Receding cryosphere: What latest WMO report warns us about

Most parts of east Africa, including Kenya, Ethiopia and Somalia, experienced 4 consecutive below-average rainfall seasons with severe humanitarian impact
Thickness Glaciers in the European Alps shrank between three and over four metres, breaking previous records. Representative photo: iStock
Thickness Glaciers in the European Alps shrank between three and over four metres, breaking previous records. Representative photo: iStock
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The global mean temperature is currently at 1.15 degrees Celcius above pre-industrial (1850-1900) levels and the last eight consecutive years were the eight hottest years of humanity, said a new report.

The cryosphere, comprising frozen parts of the earth — such as glaciers, snow and permafrost — also receded drastically, according to the latest World Meteorological Organisation’s (WMO) Provisional State of the Global Climate in 2022 report.

It was the first time that “no snow outlasted the summer season even at the very highest measurement sites and thus no accumulation of fresh ice occurred,” the WMO said.

The lack of adequate winter snow and Saharan dust blowing over the Alps accelerated the same this year. Heat waves between May and early September 2022 led to massive ice loss, too, the report said.

Glaciers in the European Alps shrank between three and over four metres, breaking previous records. Some six per cent of the glacier ice volume melted in the Alpine region of Switzerland between 2021 and 2022, the report noted.

The volume of glacier ice in Switzerland decreased from 77 cubic kilometres (km3) to 49 km3 — a decline of more than a third between 2001 and 2022.

El Niño and La Niña are the two prominent weather phenomena that influence climate change. They are generally associated with increasing droughts, floods and rainfall.

El Niño is the warming of the sea surface near the eastern tropical Pacific Ocean, which results in the weakening of trade winds. La Nina is the cooling of the central and eastern tropical Pacific Ocean, which strengthens the trade winds.

A rare triple-dip cooling La Niña was experienced for the third consecutive year in 2022, with repercussions across the world. This is the third time the event has occurred in the last 50 years after 1973-76 and 1998-2001.

La Niña does not necessarily lower temperatures everywhere. In New Zealand, it is associated with warmer temperatures.

“The country reported its fifth warmest summer (2020/2021), followed by its second warmest autumn and its warmest and wettest winter on record,” the report said.

This marked the third consecutive winter to break the temperature record, the report added.

Most parts of east Africa, including Kenya, Ethiopia and Somalia, “experienced four consecutive below-average rainfall seasons with severe humanitarian impact,” it added.

The Indian Ocean Dipole (IOD) results in below-average sea surface temperatures at a western pole in the Arabian Sea and above-average sea surface at an eastern pole in the eastern Indian Ocean south of Indonesia. It is characterised by a difference in sea surface temperatures between the western and eastern Indian Oceans. 

“Positive IOD events are often associated with El Niño and negative events with La Niña. For the second consecutive year, a negative IOD developed during austral winter,” the report said.

Austral winter is the winter in the southern hemisphere, between June-September.

“In combination with La Niña, this phase contributed to wet conditions across much of Australia in late austral winter and spring,” the report said.

It was the wettest winter since 2016 for both Queensland and the Northern Territory, it added.

“The negative IOD, again in combination with La Niña, is contributing once again to the extremely dry conditions in eastern Africa,” the report added.

Regional catastrophes

China experienced a record-breaking hot summer from mid-June to August end — with 20 per cent to 50 per cent below average rainfall in southern China, particularly in the Yangtze River valley, Wuhan.

Southern Africa witnessed several cyclones within two months. It led to worrying amounts of climate migration and refugees, otherwise known as internally displaced persons (IDP).

Madagascar witnessed four landfalls in the space of a month in late January and February.

“Cyclone Ana (January) and Cyclone Batsirai (February) have caused significant loss of life there, with Ana also going on to have major impacts from flooding in Mozambique and Malawi,” the report said.

Two months after the storm had displaced over 20,000 IDP households in Mozambique, 736,000 people were affected by Tropical Cyclone Gombe in Nampula and Zambezia provinces, the report added.

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